git: 43c00fbfe676 - stable/15 - bufspace_wait(): only try to help bufdaemon if there is a chance to help

The branch stable/15 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=43c00fbfe6763570b9cf69ec7bbfb7d62a3d8ca9

commit 43c00fbfe6763570b9cf69ec7bbfb7d62a3d8ca9
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2026-04-22 05:09:34 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-05-14 00:48:03 +0000

    bufspace_wait(): only try to help bufdaemon if there is a chance to help
    
    (cherry picked from commit ce4e8c478a261ce6c7af7d81817f86420c5239b9)
---
 sys/kern/vfs_bio.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c
index 2368f863a248..5b8d4a87c1ab 100644
--- a/sys/kern/vfs_bio.c
+++ b/sys/kern/vfs_bio.c
@@ -727,7 +727,8 @@ bufspace_wait(struct bufdomain *bd, struct vnode *vp, int gbflags,
 	BD_LOCK(bd);
 	while (bd->bd_wanted) {
 		if (vp != NULL && vp->v_type != VCHR &&
-		    (td->td_pflags & TDP_BUFNEED) == 0) {
+		    (td->td_pflags & TDP_BUFNEED) == 0 &&
+		    vp->v_bufobj.bo_dirty.bv_cnt > 0) {
 			BD_UNLOCK(bd);
 			/*
 			 * getblk() is called with a vnode locked, and